How it grew: The U.S. government accounts for some 90% of sales at iNetworks Group Inc., a reseller of broadband and other telecom services to agencies like the Pentagon. The company finds cut-rate prices from regular carriers for underutilized fiber and switches and directs public traffic on those networks. CEO David Smat, 46, figures the rising pressure to cut government budget deficits will make his service more compelling in the coming year.

"Government agencies are migrating from old-style phone systems to things like voice over Internet protocol. They're also allowing more workers to telecommute from home," Mr. Smat says. "All of that requires the sort of program management and additional information technology capabilities that we can offer."

For the first time, Mr. Smat is talking about pushing iNetworks beyond reselling. He says the company may begin acquiring some of its own assets, like optical switching equipment. It also may move into wireless, a market it's avoided so far.